The present invention generally pertains to sewing systems. More specifically, the present invention pertains to sewing systems which sew a curved edge on a cloth piece. In embodiments, the curved edge sewing systems sew a curved edge of a fly. The present invention also pertains to methods of sewing curved edges on flies or other cloth pieces.
Pieces of cloth, such as a fly for pants, have been sewed along a curved edge. The fly typically has a rectangular strip-like shape with one corner cut in a circular arc shape. An edge of the fly including the edge of the circular arc is sewed. Existing sewing of the fly is accomplished by a sewing operator manually rotating the strip-like fly relative to a sewing needle as the edge is sewed. The manual operation of rotating the strip-like fly is subject to variability depending on differences in technique and ability of the sewing operators. The quality and consistency of the curved sewed edge can vary and may not be acceptable. Also, the operator must have a relatively high level of skill to manually rotate the curved edge for sewing.
An edge sewing apparatus for sewing an edge of a cloth piece in a strip-like shape, such as a fly, along one side edge thereof in a curved shape is disclosed in U.S. patent application Ser. No. 11/482,457, filed Jul. 7, 2006. The edge sewing apparatus provides edge sewing in a curved shape along one side edge of a cloth piece in a strip-like shape while rotating the cloth piece. The edge sewing apparatus includes a press rotating member rotated in accordance with feeding of the cloth piece while pressing the cloth piece, a rotational angle measuring device that measures a rotational angle of the press rotating member, and a press releasing device that releases the press rotating member from being pressed when the rotational angle measured by the rotational angle measuring device reaches a predetermined angle. A cloth feeding mechanism at the sewing needle feeds the cloth piece passed the sewing needle. When the cloth piece is held by the press rotating member, the cloth feeding mechanism rotates the cloth piece which results in the rotation of the press rotating member. The press rotating member is free to rotate, and rotates due to the cloth being fed by the cloth feeding mechanism. The press rotating member does not drive the rotation of the cloth piece. Accordingly, the edge sewing apparatus does not have a mechanism which drives the press rotating member to drive rotation of the cloth piece. The edge sewing apparatus utilizes the cloth feeding mechanism to rotate the cloth piece which can result in inconsistent rotation and inconsistent edge sewing of the cloth piece. Also, the operator has to manually assist the rotation of the cloth piece which can also result in inconsistencies in rotation of the cloth piece and edge sewing. The quality of the sewed curved edge may be degraded due to the inconsistency and manual assistance by the operator.
Accordingly, needs exist to improve curved edge sewing systems for the reasons mentioned above and for other reasons.